Molecular structures of [(tBu)2Ga(μ-O2CPh)]2, [(tBu)2Ga(μ-O2CC6H4-3-CN)]2, and [(tBu)2Ga(μ-SC6H5)]2:: The efficacy of oxygen and sulfur donor ligands for binding GaAs and GaS surfaces

The reaction of Ga(Bu-t)(3) with 1 molar equivalent of a carboxylic acid yields the carboxylate bridged dimeric compounds, [(Bu-t)(2)Ga(mu-O2CR)](2), where R-Ph (I), C6H4-3-CN (2), and C6H4-3-Br (3), respectively. Similarly, reaction of Ga(Bu-t)(3) with HSPh yields the thiolate bridged compound, [(Bu-t)(2)Ga(mu-SPh)](2) (4). The molecular structures of compounds 1, 2, and 4 have been determined by X-ray crystallography. The Ga ... Ga and Ga-ligand inter-atomic distances for these compounds, as well as group 15 and 16 donor bridging ligands, are compared to the values for the surface of GaAs and cubic-GaS in order to determine their suitability as linkage groups for self-assembled monolayers. (C) 1998 Elsevier Science Ltd. All rights reserved.